The minesweeper JS Ukushima, seen in an undated photo, caught fire and eventually sank on November 11, 2024. (Japanese Ministry of Defense)

TOKYO — A joint U.S.-Japan naval exercise was canceled after a Japanese sailor went missing over the weekend after a fire broke out aboard a minesweeper that eventually sank.

The U.S. and Japanese navies were scheduled to conduct minesweeping training between Saturday and Tuesday, before the JS Ukushima caught fire on Sunday and sank the next day. The ship’s crew received training en route to the joint exercise, a Maritime Self-Defense Force spokesman told Stars and Stripes by phone on Tuesday.

The exercise was canceled due to efforts to locate Petty Officer 3rd Class Tatsunori Koga, 33, who worked in the ship’s engine room, the command said in a news release.

A sailor working in the same room was also injured; The remaining 43 crew members were evacuated safely, the spokesman said. It is a tradition in Japan for some government officials to speak to the media anonymously.

The fire started around 9:45 a.m. Sunday in waters 1.5 miles north of Oshima in Fukuoka prefecture, part of Kyushu, the southernmost of Japan’s four main islands. The fire was extinguished around midnight Monday, but the ship eventually sank around 8.34am, the spokesman said.

According to the spokesman, Ukushima was built with a wooden hull.

The Maritime Self-Defense Force and Japan’s coast guard were still searching for Koga Tuesday afternoon.

The fire is believed to have started in the engine room where the ship’s diesel engines are located, Chief Cabinet Secretary Yoshimasa Hayashi said at a news conference on Monday.

“The Government of Japan will do its best to search for the missing personnel and take all possible measures to determine the cause and take preventive measures,” he said.

Hayashi said the Self-Defense Force formed a committee to investigate the cause of the fire.

The US 7th Fleet acknowledged an email from Stars and Stripes asking if the US would assist in the search or continue the exercise. The command had not responded as of close of business Tuesday.